DCHECK_LE for cr_ngroups vs arraysize(cr_groups)

DCHECK_LE for cr_ngroups vs arraysize(cr_groups)

This DCHECK fails for me locally as

[----------] 3 tests from ProcessInfo
[ RUN      ] ProcessInfo.Self
[70989:10546846:20141216,112509.948519:FATAL process_info_mac.cc:114] Check failed: static_cast<size_t>(ngroups) < (sizeof(ArraySizeHelper(kern_proc_info_.kp_eproc.e_ucred.cr_groups))) (16 vs. 16).
Abort trap: 6

It doesn't seem to happen on the waterfall, so maybe I'm building against
an incorrect header? I don't particularly understand the code, but assuming
it's normal 0-based array, perhaps it should be a DCHECK_LE in any case.

R=mark@chromium.org

Committed: https://chromium.googlesource.com/crashpad/crashpad/+/4a5d21528e5a7da84352a447c0df2e341159a53e

[Mark Mentovai, 2014-12-16 19:53:38]

The headers are fine. What does it show when you run “id?” How many groups are
in the “groups” list?

[Mark Mentovai, 2014-12-16 20:14:52]

DCHECK_LE is correct. LGTM.

[scottmg, 2014-12-16 20:18:37]

Committed patchset #1 (id:1) manually as
4a5d21528e5a7da84352a447c0df2e341159a53e (presubmit successful).